1. Field of the Invention
The present invention relates to a data reproducing apparatus for reproducing a content stored in a recording medium by an image capturing apparatus such as a digital camera or the like, and a content management method.
2. Description of the Related Art
In image capturing apparatuses such as digital still cameras, digital video cameras, and the like, since a recordable data size dramatically increases with increasing number of pixels of image capturing elements, the capacities of recording media that is available for use in the image capturing apparatuses have increased accordingly. Also, a plurality of storages can be used to attain a large capacity, and a method that uses a large-capacity external storage device connected via a digital interface in addition to a recording medium that uses an internal slot of the image capturing apparatus is prevalent.
Recent image capturing apparatuses can use external storage devices such as a hard disk (HDD) and the like via a high-speed serial interface such as Universal Serial Bus (USB), IEEE1394, and the like simultaneously with internal recording media such as a memory card, disk, tape, and the like.
FIG. 1 shows an arrangement in which a digital camera 101 that uses a random access medium 102 as a recording medium and an external storage device 104 are connected via a USB interface cable 103. Both the digital camera 101 and external storage device 104 comprise USB interfaces, as a matter of course.
The digital camera 101 serves as a USB host, and the large-capacity external storage device 104 serves as a USB device (slave). When the USB host acquires data from the USB device via the USB interface, it is a common practice to make communications according to the standards such as PTP, Mass Storage, and the like. Note that PTP is a standard specified by “Universal Serial Bus Still Image Capture Device Definition Revision 1.0 Jul. 11, 2000”. Also, Mass Storage is a standard specified by “Universal Serial Bus Mass Storage Class Bulk-Only Transport Revision 1.0 Sep. 31, 1999”.
A case of communications compliant to Mass Storage will be explained below with reference to FIG. 1.
Upon detecting the connection of the external storage device 104 via the USB interface cable 103, the digital camera 101 acquires descriptor information from the external storage device 104. The digital camera 101 determines device information and a communication method, and recognizes the external storage device 104 as a device of Mass Storage Class. After that, the digital camera 101 acquires data according to Mass Storage. In this case, the digital camera 101 accesses all image data stored in the external storage device 104 via its internal file system.
The digital camera 101 also connects the random access medium 102 as a storage, and allows the user to display and browse image data via its internal file system. The user manipulates the digital camera 101 to designate a storage used to save and browse captured image data, and can also record the same image in a plurality of storages at the same time. The user individually designates the random access medium 102 and external storage device 104, thus freely manipulating saved image data.
With digital devices, it is a common practice to back up data and to control respective devices via a network. Consumer devices such as a digital still camera, digital video camera, and the like are also connected to the network and can communicate with external devices. Especially, by building up an IP network using an Internet Protocol (to be abbreviated as IP hereinafter), many devices are connected to each other and can exchange data. For example, in some system, the user can browse, via a personal computer (to be abbreviated to as PC hereinafter) or the like, moving image data stored in one external storage device such as a home server or the like connected to a tuner by converting the moving image data into a displayable format according to each external device (for example, Japanese Patent Laid-Open No. 2005-065008).
Like in the home server, the user can also browse image data stored in a digital still camera using an external device via the network. Digital devices undergo extensions such as support of interfaces that allow IP connections such as Ethernet®, Wireless LAN, and the like in addition to a serial bus network such as USB, IEEE1394, and the like. By providing, in a common format, an image designated by an acquisition request from an external device, images can be displayed on the external device.
However, upon issuing an acquisition request of a plurality of images stored in a plurality of recording media in addition to the designated image, if the plurality of recording media store identical images, the external device acquires all images including the identical images. Also, the external device displays the identical images simultaneously stored in the plurality of recording media. For this reason, when the user visually confirms images displayed on a display of the external device, he or she cannot discriminate their differences, resulting in confusion. Especially, when the external device adopts a display method that does not show image file names, attributes, and the like, a plurality of identical images are acquired, thus requiring a long time to acquire and display data.